<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="https://unpkg.com/vue@3"></script>
</head>
<body>
  <div id="app">
    <span v-for="item in count" @click="handleClick">{{ item }}</span>
  </div>

  <script type="module">
    const { createApp, ref, onMounted } = Vue
    createApp({
      setup() {
        const count = ref(['hello'])

        const handleClick = () => {
          count.value.push(new Date().getTime())
          console.log(count)
        }

        onMounted(() => {
          console.log('mounted')
        })

        return {
          count,
          handleClick
        }
      }
    }).mount('#app')
  </script>
</body>
</html>